Ai Weiwei (Chinese: 艾未未; pinyin: Ài Wèiwèi; About this sound English pronunciation ), born 18 May 1957 in Beijing, is a Chinese contemporary artist, active in sculpture, installation, architecture, curating, photography, film, and social, political and cultural criticism. Ai collaborated with Swiss architects Herzog & de Meuron as the artistic consultant on the Beijing National Stadium for the 2008 Olympics. As a political activist, he has been highly and openly critical of the Chinese Government's stance on democracy and human rights. He has investigated government corruption and cover-ups, in particular the Sichuan schools corruption scandal following the collapse of so-called "tofu-dreg schools" in the 2008 Sichuan earthquake. In 2011, following his arrest at Beijing Capital International Airport on 3 April, he was held for 81 days without any official charges being filed; officials alluded to their allegations of "economic crimes".